<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .box {
            width: 200px;
            height: 26px;
            position: relative;
            background-color: red;
            border: 1px solid red;
            text-align: center;
            line-height: 26px;
        }

        .left {
            float: left;
            position: relative;
            width: 100px;
        }

        .left i {
            position: absolute;
            right: 0;
            width: 0;
            height: 0;
            border-color: transparent #fff transparent transparent;
            border-style: solid;
            border-width: 26px 10px 0 0;
        }

        .right {
            float: left;
            width: 100px;
            height: 26px;
            background-color: #fff;
        }
    </style>
</head>

<body>
    <div class="box">
        <div class="left">
            秒杀
            <i></i>
        </div>
        <div class="right">
            原价
        </div>
    </div>
</body>

</html>